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Darren Seibert
07-27-2012, 8:01 AM
Greetings Ya'll! I'm excited to finally join the Creek to learn how to make myself a better engraver. I have a bit of a question that I cannot find the answer too. I am an owner of a 55w ULS V-4.60 and enjoy using it on all substrates except one. MARBLE!!! While engraving text on marble is not an issue, over the last couple of years I can never lick this photo engraving on marble deal. I have read through "most" of the Marble Photo threads and even tried numerous settings that ya'll have provided to no avail. I seem to get closest using a 300 dpi image with the engraver settings at 50 p, 100 s, 500 ppi and an image density of 2 and my print driver set to b&w instead of halftone or error diffusion. I have the old ULS print driver and I think I just don't understand PPI and Image density properly. Normally, I leave those settings alone....but I am trying everything to make my engraving look half as good as ya'lls. Argh. Any assistance ya'll could provide this frustrated engraver would be great appreciated especially if you have experience with the old ULS print driver. Thanks and God Bless.

Scott Shepherd
07-27-2012, 8:07 AM
I haven't used that old print driver, but if it's the same as now, Image Density of 2 would be an issue. No less than 3, probably 4 is what you should be using if it's the same scale as used today, 1 being the worst (5,6, or 7, depending on the latest driver) is the highest resolution.

Marble should be beautiful coming off that machine. It should look just like a photograph. It is true marble or something that's really granite, called Marble? There's a company that sells laser tiles that markets a marble tile, but it's really granite. If it's true marble, the photos will be stunning in detail. If you can't get any detail or shading of gray areas, then it's probably granite being called marble.

Dee Gallo
07-27-2012, 9:46 AM
According to my notes, it looks like you have your settings backwards. I don't have your power, but I use 25 speed and 100 power for marble. The settings you quote are more for granite. I know, this is the reverse of what the manual says.

Mike Ireland
07-27-2012, 11:35 AM
Hi Darren,
PPI (pulses per inch) would be your horizontal pixels - the higher this number the more times the laser will pulse. Image Density is best described as how many lines per inch vertically. The higher this number, the more lines you will have in the image as it goes down the page. Photos on marble usually look great. There are a few items to consider. To much power and you can blow out the details. I would start with settings of about 50% power and 100% speed, PPI at 500 and ID at 5. Make sure you have good marble that is mostly black - white marks will detract from the image. Finally, once the image is complete, try rubbing in a small amount of white oil paint - we use titanium white available at Michael's to really make the image pop.

Darren Seibert
07-27-2012, 11:37 AM
Thanks Scott and Dee. I will make changes you advised and report back later. Really want to figure this out as I have many customers asking me for this.

Darren Seibert
07-27-2012, 11:45 AM
Thanks Mike but I've read that I might have granite and not marble....with that being said, should I swap the power and speed settings and try that. Also, should I be using halftone, error diffusion or black and white in the advanced tabs to get the best results?

Scott Shepherd
07-27-2012, 12:42 PM
Go here :

http://www.sawmillcreek.org/showthread.php?111964-1-Touch-Photo/page3&highlight=marble

Scroll down to post #37 and look at the 2 photos I posted. That's what marble looks like when engraved. If you don't see all those shades of gray, you probably have granite.

Darren Seibert
07-27-2012, 1:33 PM
Steve, your right it's Granite....Double Argh...and it wasn't from Laser Sketch :)